This application claims benefit of priority to Japanese Patent Application No. 2020-142632, filed Aug. 26, 2020, the entire content of which is incorporated herein by reference.
The present disclosure relates to an inductor component.
The inductor component described in Japanese Patent No. 6024243 has a base body with a main surface. A first inductor wiring and a second inductor wiring are disposed in the base body. The first inductor wiring and the second inductor wiring extend in parallel to the main surface. In addition, the first inductor wiring and the second inductor wiring extend spirally. The layer of the first inductor wiring and the layer of the second inductor wiring are disposed in the direction orthogonal to the main surface.
In an inductor component such as the one described in Japanese Patent No. 6024243, a second inductor wiring is present in addition to a first inductor wiring in the base body. When the wiring length of the second inductor wiring is long, if the external shape of the inductor component is the same, the ratio of the volume of the magnetic material in the base body to the volume of the inductor component becomes smaller. Accordingly, the inductance of the inductor component is not as high as expected even though the second inductor wiring is provided in addition to the first inductor wiring, thereby reducing the inductance acquisition efficiency.
According to preferred embodiments of the present disclosure, there is provided an inductor component including a base body having a main surface; an inductor wiring extending in parallel to the main surface in the base body; a first vertical wiring connected to a first end of the inductor wiring, the first vertical wiring being exposed through the main surface; and a second vertical wiring connected to a second end of the inductor wiring, the second vertical wiring being exposed through the main surface. The base body has a magnetic layer disposed closer to the main surface than the inductor wiring. The first vertical wiring and the second vertical wiring have columnar shapes extending in a thickness direction while penetrating the magnetic layer, the thickness direction being orthogonal to the main surface. A dimension in the thickness direction of a penetration portion is five times or more a maximum dimension in the thickness direction of the inductor wiring, the penetration portion being a portion of the first vertical wiring penetrating the magnetic layer.
In the structure described above, the dimension in the thickness direction of the penetration portion of the first vertical wiring has a reasonable size as compared with the dimension in the thickness direction of the inductor wiring. By increasing the dimensions in the thickness direction of the first vertical wiring so as to actively configure the first vertical wiring as a wiring that contributes to inductance as described above, the inductance can be improved. Meanwhile, since the first vertical wiring has a columnar shape extending in the thickness direction and not in parallel to the main surface of the base body, it is possible to suppress the volume of the magnetic layer from becoming excessively small due to the presence of the first vertical wiring. As a result, the occurrence of a situation in which an expected inductance cannot be obtained due to reduction in the volume of the magnetic layer can be suppressed.
Reduction in the inductance acquisition efficiency can be suppressed.
Other features, elements, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of preferred embodiments of the present disclosure with reference to the attached drawings.
Embodiments of an inductor component will be described below. It should be noted that the drawings may be illustrated with enlarged components for ease of understanding. The dimension ratios of components may differ from those of actual components or those of components in another figure.
An inductor component according to a first embodiment will be described below.
As illustrated in
A first layer L1 is disposed as the lowermost layer of the four layers. The first layer L1 is substantially rectangular when viewed in the thickness direction Td. The direction along the long side of this substantially rectangular shape is a longitudinal direction Ld and the direction along the short side is a lateral direction Wd.
The first layer L1 includes only a lower magnetic layer 21. The lower magnetic layer 21 is a mixture of resin and metal magnetic powder and is a magnetic material as a whole. In the embodiment, the dimension in the longitudinal direction Ld of the first layer L1 is about 600 μm, the dimension in the lateral direction Wd of the first layer L1 is about 300 μm, and the dimension in the thickness direction Td of the first layer L1 is about 220 μm.
A second layer L2 is laminated on the upper surface, which is the surface on the upper side in the thickness direction Td of the first layer L1. The second layer L2 is substantially rectangular when viewed in the thickness direction Td, which is the same as the first layer L1. The second layer L2 includes an inductor wiring 30 and an intermediate magnetic layer 22. The inductor wiring 30 is included only in the second layer L2. That is, the inductor wiring 30 is a single layer.
As illustrated in
The first end of the wiring body 31 is connected to the side surface in the lateral direction Wd of the first pad 32 close to the second end. The wiring width of the wiring body 31 is smaller than the diameter of the first pad 32. When viewed from the upper side in the thickness direction Td, the wiring body 31 extends clockwise from the outer side portion to the inner side portion substantially spirally around the vicinity of the center of the second layer L2.
The second pad 33 is connected to the second end of the wiring body 31. The shape of the second pad 33 is substantially circular when viewed in the thickness direction Td, which is the same as that of the first pad 32. The second pad 33 is disposed closer to the second end in the longitudinal direction Ld than the middle in the longitudinal direction Ld of the second layer L2. In addition, the second pad 33 is disposed near the middle in the lateral direction Wd of the second layer L2.
The number of turns of the inductor wiring 30 is determined based on a virtual vector. The starting point of the virtual vector is disposed on the virtual center line that extends in the extension direction of the inductor wiring 30 through the middle of the wiring width of the inductor wiring 30. When viewed in the thickness direction Td, if the virtual vector is moved from the state in which the starting point of the inductor wiring 30 is disposed at one end to the other end of the virtual center line, the number of turns is defined as 1.0 turns when the rotation angle of the orientation of the virtual vector is 360 degrees. Accordingly, when the inductor wiring 30 is wound by, for example, 180 degrees, the number of turns is 0.5 turns. In the embodiment, the orientation of the virtual vector virtually disposed on the inductor wiring 30 is rotated by 450 degrees. Accordingly, the number of turns by which the inductor wiring 30 is wound is 1.25 turns in the embodiment.
In addition, the portion of the inductor wiring 30 from the first pad 32 to the 0.25 turns of the wiring body 31 and the portion of the inductor wiring 30 from the second pad 33 to 0.25 turns of the wiring body 31 extend in parallel to each other. The inter-wiring distance of the inductor wiring 30 is minimum between the inner side surface in the radial direction of the portion from the first pad 32 to 0.25 turns of the wiring body 31 and the outer side surface in the radial direction of the portion from the second pad 33 to 0.25 turns of the wiring body 31.
The maximum dimension TI in the thickness direction Td of the inductor wiring 30 illustrated in
As illustrated in
A third layer L3 is laminated on the upper surface, which is the surface on the upper side in the thickness direction Td of the second layer L2. The third layer L3 is substantially rectangular when viewed in the thickness direction Td, which is the same as the second layer L2. The third layer L3 includes a first vertical wiring 41, a second vertical wiring 42, and an upper magnetic layer 23.
The first vertical wiring 41 is directly connected to the upper surface of the first pad 32 of the inductor wiring 30 without intervention of any other layer. That is, the first vertical wiring 41 is connected to the first end of the inductor wiring 30. The material of the first vertical wiring 41 is a conductive material. In the embodiment, the first vertical wiring 41 has a composition of not less than about 99 wt % of copper. That is, the first vertical wiring 41 contains not less than about 99 wt % of copper.
The first vertical wiring 41 has a substantially cylindrical shape and the axial direction of the substantially cylindrical shape matches the thickness direction Td. That is, the lower surface of the first vertical wiring 41 is in direct contact with the inductor wiring 30. As illustrated in
The second vertical wiring 42 is directly connected to the upper surface of the second pad 33 of the inductor wiring 30 without intervention of any other layer. That is, the second vertical wiring 42 is connected to the second end of the inductor wiring 30. The material of the second vertical wiring 42 is a conductive material. In the embodiment, the second vertical wiring 42 has a composition of not less than about 99 wt % of copper. That is, the second vertical wiring 42 contains not less than about 99 wt % of copper.
The second vertical wiring 42 has a substantially cylindrical shape and the axial direction of the substantially cylindrical shape matches the thickness direction Td. That is, the lower surface of the second vertical wiring 42 is in direct contact with the inductor wiring 30. As illustrated in
As illustrated in
That is, the first vertical wiring 41 and the second vertical wiring 42 extend in the thickness direction Td while penetrating the upper magnetic layer 23 in the thickness direction Td. In addition, in the embodiment, the entire first vertical wiring 41 and the entire second vertical wiring 42 are penetration portions PP that penetrate the upper magnetic layer 23. Accordingly, the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 is the same as the dimension TV1 in the thickness direction Td of the first vertical wiring 41. Accordingly, the ratio of the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 to the diameter D1, which is the width dimension in the direction orthogonal to the thickness direction Td of the first vertical wiring 41, is about 2.2. Similarly, the dimension in the thickness direction Td of the penetration portion PP of the second vertical wiring 42 is the same as the dimension TV2 in the thickness direction Td of the second vertical wiring 42. Accordingly, the ratio of the dimension in the thickness direction Td of the penetration portion PP of the second vertical wiring 42 to the diameter D2, which is the width dimension in the direction orthogonal to the thickness direction Td of the second vertical wiring 42, is about 2.2. The width dimension of each of the vertical wirings is the smallest dimension of the Feret's diameter in the direction parallel to the main surface MF. The Feret's diameter in the direction parallel to the main surface MF is the smallest dimension of the dimensions in the direction orthogonal to the thickness direction Td of the images generated when the individual vertical wirings are projected in the direction parallel to the main surface MF.
Furthermore, the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 is about 7.3 times the dimension in the thickness direction Td of the inductor wiring 30. Similarly, the dimension in the thickness direction Td of the penetration portion PP of the second vertical wiring 42 is about 7.3 times the dimension in the thickness direction Td of the inductor wiring 30.
In addition, the lower magnetic layer 21, the intermediate magnetic layer 22, and the upper magnetic layer 23 described above constitute a magnetic layer 20. The upper magnetic layer 23 is disposed above the inductor wiring 30 and the upper magnetic layer 23 is the first magnetic layer. The interfaces between individual layers may be present or absent in the magnetic layer 20. In the embodiment, the lower magnetic layer 21 and the intermediate magnetic layer 22 are integrated with each other and no interface is present. In contrast, an interface is present between the intermediate magnetic layer 22 and the upper magnetic layer 23.
A fourth layer L4 is laminated on the upper surface, which is the surface on the upper side in the thickness direction Td of the third layer L3. The fourth layer L4 includes a first external terminal 51, a second external terminal 52, and an insulating layer 60.
As illustrated in
The second external terminal 52 is disposed in a range including the entire upper surface of the second vertical wiring 42 of the upper surface of the third layer L3. The second external terminal 52 has a substantially rectangular shape with a long side along the lateral direction Wd when viewed in the thickness direction Td. The dimensions of the sides of the second external terminal 52, which is substantially rectangular when viewed in the thickness direction Td, are larger than the diameter D2 of the second vertical wiring 42. Accordingly, the second external terminal 52 is disposed on the entire upper surface of the second vertical wiring 42 and part of the upper surface of the upper magnetic layer 23. The second external terminal 52 is disposed closer to the second end than the middle in the longitudinal direction Ld of the fourth layer L4. Although not illustrated, the second external terminal 52 has a three-layer structure containing copper, nickel, and gold. The dimension in the thickness direction Td of the second external terminal 52 is about 10 μm.
As illustrated in
The dimension in the thickness direction Td of the insulating layer 60 illustrated in
In addition, the dimension TA in the thickness direction Td of the inductor component 10 illustrated in
Next, the manufacturing method for the inductor component 10 according to the first embodiment will be described.
In manufacturing the inductor component 10, a base member preparation process is first performed. Specifically, a plate-like base member 81 as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, a resin containing magnetic powder, which is the material of the upper magnetic layer 23, is applied as a first magnetic layer forming process. As illustrated in
Next, as illustrated in
Next, a seed layer forming process for forming a seed layer is performed. Specifically, copper seed layers are formed on the lower surface of the first vertical wiring 41, the lower surface of the second vertical wiring 42, and the lower surface of the upper magnetic layer 23 by sputtering. It should be noted that the seed layer is not illustrated because the layer is much thinner than other layers.
Next, a covering process is performed to form a covering portion 83 that covers the portion of the lower surface of the seed layer in which the inductor wiring 30 is not to be formed, as illustrated in
Next, an inductor wiring work process is performed to form the inductor wiring 30 in the portion of the lower surface of the seed layer that is not covered with the covering portion 83 by electrolytic plating. Specifically, electrolytic copper plating is performed to cause copper to be grown from the portion of the seed layer that is not covered with the covering portion 83.
Next, a covering portion removal process for removing the covering portion 83 is performed, as illustrated in
Next, a seed layer etching process for etching the seed layer is performed. The seed layer exposed through the grown copper portion is removed by etching the seed layer. This forms the inductor wiring 30. That is, in the embodiment, the inductor wiring 30 is formed by a semi additive process (SAP).
Next, a second magnetic layer work process is performed to laminate the lower magnetic layer 21 on the intermediate magnetic layer 22 as illustrated in
Next, a base member removal process is performed. Specifically, the base member 81 and the adhesive layer 82 are removed. As illustrated in
Next, after the base member removal process, an insulating layer work process is performed with the entire body turned upside down in the thickness direction Td, as illustrated in
Next, as an external terminal forming process, the first external terminal 51 is formed in the range including the upper surface of the first vertical wiring 41, and the second external terminal 52 is formed in the range including the upper surface of the second vertical wiring 42. The first external terminal 51 and the second external terminal 52 are formed by electroless plating for copper, nickel, and gold. This forms the external terminals with a three-layer structure. It should be noted that
Next, an individualizing work process is performed as illustrated in
Next, the operation and effects of the inductor component 10 according to the first embodiment described above will be described.
(1-1) According to the first embodiment described above, the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 is about 7.3 times the maximum dimension TI in the thickness direction Td of the inductor wiring 30. That is, the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 is about five times or more the maximum dimension TI in the thickness direction Td of the inductor wiring 30. Accordingly, the dimension in the thickness direction Td of the first vertical wiring 41 has a reasonable size as compared with the dimension in the thickness direction Td of the inductor wiring 30. By actively configuring the first vertical wiring 41 as the wiring that contributes to inductance as described above by increasing the dimension in the thickness direction Td of the first vertical wiring 41, the improvement of inductance can be achieved. Meanwhile, since the first vertical wiring 41 has a substantially columnar shape extending in the thickness direction Td and not in parallel to the main surface MF of the base body BD, it is possible to suppress the volume of the upper magnetic layer 23 from becoming excessively small due to the presence of the first vertical wiring 41. As a result, it is possible to suppress the occurrence of a situation in which an expected inductance cannot be obtained due to reduction in the volume of the upper magnetic layer 23.
In addition, the base body BD has the magnetic layer 20. The dimension in the thickness direction Td of the upper magnetic layer 23 that is penetrated by the penetration portion PP of the first vertical wiring 41 of the magnetic layer 20 is also about five times or more the dimension in the thickness direction Td of the inductor wiring 30. Accordingly, the inductor wiring 30 is covered with the reasonably thick upper magnetic layer 23 from the upper side in the thickness direction Td. Accordingly, since the magnetic flux generated when a current flows through the inductor wiring 30 is shielded by the upper magnetic layer 23, the amount of magnetic flux emitted outside the inductor component 10 can be reduced.
(1-2) According to the first embodiment described above, the ratio of the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 to the diameter D1, which is the width dimension in the direction orthogonal to the thickness direction Td of the first vertical wiring 41, is about 2.2. The dimension TV1 in the thickness direction Td of the first vertical wiring 41 is about 220 μm. Accordingly, the first vertical wiring 41 extends in the thickness direction Td reasonably long. The inductance can be improved by ensuring the wiring length of the first vertical wiring 41 as described above.
(1-3) According to the first embodiment described above, the dimension in the thickness direction Td of the penetration portion PP of the first vertical wiring 41 is about 7.3 times the maximum dimension TI in the thickness direction Td of the inductor wiring 30. Similarly, the dimension in the thickness direction Td of the penetration portion PP of the second vertical wiring 42 is about 7.3 times the maximum dimension TI in the thickness direction Td of the inductor wiring 30. That is, the dimension in the thickness direction Td of the penetration portion PP of each of the vertical wirings is about seven times or more the maximum dimension TI in the thickness direction Td of the inductor wiring 30. By increasing the dimension in the thickness direction Td of each of the vertical wirings as described above, the dimension in the thickness direction Td of the upper magnetic layer 23 penetrated by each of the vertical wirings also becomes larger. As a result, the dimension in the thickness direction Td of the upper magnetic layer 23 becomes reasonably large with respect to the maximum dimension TI in the thickness direction Td of the inductor wiring 30 and the amount of the upper magnetic layer 23 can be ensured.
(1-4) According to the first embodiment described above, the maximum dimension TI in the thickness direction Td of the inductor wiring 30 is about 30 μm. In addition, the portion of the second layer L2 excluding the inductor wiring 30 is the intermediate magnetic layer 22. Accordingly, the maximum dimension in the thickness direction Td of the intermediate magnetic layer 22 matches the maximum dimension TI in the thickness direction Td of the inductor wiring 30. Since the maximum dimension TI in the thickness direction Td of the inductor wiring 30 is not less than about 10 μm, the DC electric resistance can be reduced reasonably. Furthermore, the intermediate magnetic layer 22 of a reasonable amount can be ensured. In contrast, since the maximum dimension TI in the thickness direction Td of the inductor wiring 30 is not more than about 50 μm, it is possible to suppress the ratio of the volume of the magnetic layer 20 to the inductor component 10 from being reduced due to the volume of the inductor wiring 30 becoming excessively large.
(1-5) According to the first embodiment described above, the dimension TBD in the thickness direction Td of the base body BD is about 475 μm, which is not more than about 500 μm. As described above, in the inductor component 10 with a comparatively small size, it is easier to obtain a high inductance because the thickness of the magnetic layer 20 of the outer magnetic path can be ensured by ensuring the dimensions in the thickness direction Td of the first vertical wiring 41 and the second vertical wiring 42 than by laminating the plurality of inductor wirings 30 in the thickness direction Td.
(1-6) According to the first embodiment described above, the first vertical wiring 41 contains not less than about 99 wt % of copper. Accordingly, since the ratio of copper composition in the first vertical wiring 41 is high, the DC current resistance of the first vertical wiring 41 can be made low reasonably. This is also true of the second vertical wiring 42.
An inductor component according to a second embodiment will be described below.
An inductor component 110 according to the second embodiment mainly differs from the inductor component 10 according to the first embodiment described above in that the inductor component 110 has a first insulating portion 171 and a second insulating portion 172 and in that a first vertical wiring 141 and a second vertical wiring 142 have different structures, as illustrated in
As illustrated in
As illustrated in
Of the outer surfaces of the inductor wiring 30, the radially inner side of the portion from the first pad 32 to a point immediately before 0.75 turns of the wiring body 31 and the radially outer side of the portion from the second pad 33 to 0.5 turns of the wiring body 31 are covered with the second insulating portion 172. That is, the second insulating portion 172 is interposed in the portion in which the inter-wiring distance of the inductor wiring 30 is minimum.
Specifically, of the outer surfaces of the inductor wiring 30, the surface excluding the upper surface and lower surface is the side surface. Of the side surface of the inductor wiring 30, the second insulating portion 172 is interposed between part of the side surface on the radially inner side of the portion from the first pad 32 to a point immediately before 0.75 turns of the wiring body 31 and part of the side surface on the radially outer side of the portion from the second pad 33 to 0.5 turns of the wiring body 31.
In addition, the second insulating portion 172 covers, of the upper surface of the inductor wiring 30, the end portion on the radially inner side of the portion from the first pad 32 to a point immediately before 0.75 turns of the wiring body 31 and the end portion on the radially outer side of the portion from the second pad 33 to 0.5 turns of the wiring body 31.
As illustrated in
In addition, as illustrated in
As illustrated in
The first columnar portion 142A has a substantially cylindrical shape and the axial direction of the substantially cylindrical shape matches the thickness direction Td. As illustrated in
The second columnar portion 142B of the second vertical wiring 142 is directly connected to the upper surface of the first columnar portion 142A. The material of the second columnar portion 142B is the same as that of the first columnar portion 142A.
The second columnar portion 142B has a substantially cylindrical shape and the axial direction of the substantially cylindrical shape matches the thickness direction Td. The diameter of the second columnar portion 142B, which is substantially circular when viewed in the thickness direction Td, is about 100 μm, which is the same as that of the first columnar portion 142A. In addition, the dimension in the thickness direction Td of the second columnar portion 142B is about 80 μm. The position of the central axis line CA2 extending in the thickness direction Td of the second columnar portion 142B deviates toward the second end in the lateral direction Wd from the central axis line CA1 of the first columnar portion 142A. Accordingly, the central axis line CA2 of the second columnar portion 142B and the central axis line CA1 of the first columnar portion 142A are not present on the same straight line. It should be noted that the amount of deviation between the central axis line CA2 of the second columnar portion 142B and the central axis line CA1 of the first columnar portion 142A is exaggerated in
The third columnar portion 142C of the second vertical wiring 142 is directly connected to the upper surface of the second columnar portion 142B. The material of the third columnar portion 142C is the same as that of the second columnar portion 142B.
The third columnar portion 142C has a substantially cylindrical shape and the axial direction of the substantially cylindrical shape matches the thickness direction Td. The diameter of the third columnar portion 142C, which is substantially circular when viewed in the thickness direction Td, is about 100 μm, which is the same as that of the second columnar portion 142B. The dimension in the thickness direction Td of the third columnar portion 142C is about 60 μm. In addition, the central axis line CA3 extending in the thickness direction Td of the third columnar portion 142C and the central axis line CA1 of the first columnar portion 142A are present on the same straight line. Accordingly, the position of the central axis line CA3 of the third columnar portion 142C deviates toward the first end in the lateral direction Wd from the central axis line CA2 of the second columnar portion 142B.
Next, the manufacturing method for the inductor component 110 according to the second embodiment will be described.
The base member preparation process is first performed as illustrated in
Next, a dummy insulating layer 182 is applied to the entire upper surface of the base member 181. Next, as illustrated in
Next, as illustrated in
Next, the second insulating portion 172 is formed as illustrated in
Next, the first vertical wiring 141 and the second vertical wiring 142 are formed as a vertical wiring process. In the second embodiment, the first vertical wiring 141 and the second vertical wiring 142 are formed by three covering processes and three plating processes. In the following description, only the second vertical wiring 142 is illustrated.
First, a first covering process is performed to form, from the upper side of the base member 181, a first covering portion 183 in the portion in which the first columnar portion 142A is not to be formed, as illustrated in
Next, a second covering process is performed to form, from the upper side of the first covering portion 183, a second covering portion 184 in the portion in which the second columnar portion 142B is not to be formed, as illustrated in
Next, a third covering process is performed to form, from the upper side of the second covering portion 184, a third covering portion in the portion in which the third columnar portion 142C is not to be formed, which is not illustrated. In the embodiment, the third covering portion is formed in the same area as the first covering portion 183 when viewed in the thickness direction Td. Next, a third plating process is performed to form the third columnar portion 142C by copper plating in the portion in which the third covering portion has not been formed. Specifically, the third columnar portion 142C is formed so as to reach the same height as the upper surface of the third covering portion. In the embodiment, the dimension in the thickness direction Td of the third columnar portion 142C formed in the third plating process is about 80 μm.
Next, the covering portion removal process is performed to remove the entire covering portion as illustrated in
Next, a first magnetic layer work process is performed to perform lamination above the lower surface of the first insulating portion 171 of the magnetic layer 20, as illustrated in
Next, the base member removal process is performed. Specifically, the base member 181 is shaved from the lower side until the first insulating portion 171 is exposed as illustrated in
Next, the second magnetic layer work process is performed to perform lamination below the lower surface of the first insulating portion 171 of the magnetic layer 20, as illustrated in
Next, the insulating layer work process is performed as illustrated in
Next, as the external terminal forming process, the first external terminal 51 is formed in the range including the upper surface of the first vertical wiring 141, and the second external terminal 52 is formed in the range including the upper surface of the second vertical wiring 142. The first external terminal 51 and the second external terminal 52 are formed by electroless plating for copper, nickel, and gold. This forms the external terminals with a three-layer structure. It should be noted that
Next, the individualizing work process is performed. Specifically, individualizing is performed by dicing along the break lines DL. As a result, the inductor component 110 can be obtained.
Next, the operation and effects of the inductor component 110 according to the second embodiment described above will be described. In the inductor component 110 according to the second embodiment, the following effects are obtained in addition to the effects (1-1) to (1-6) of the inductor component 10 according to the first embodiment described above.
(2-1) According to the second embodiment described above, the second vertical wiring 142 includes the first columnar portion 142A, the second columnar portion 142B, and the third columnar portion 142C. Accordingly, the dimension in the thickness direction Td can be easily increased by forming the second vertical wiring 142 through a plurality of processes. This is also true of the first vertical wiring 141.
(2-2) According to the second embodiment described above, the three columnar portions constituting the second vertical wiring 142 have a substantially cylindrical shape and the axial direction of the substantially cylindrical shape matches the thickness direction Td. In addition, the central axis line CA2 of the second columnar portion 142B and the central axis line CA1 of the first columnar portion 142A are not present on the same straight line. Accordingly, the region in which the second vertical wiring 142 is present can be distributed as compared with the case in which the central axis line CA2 matches the central axis line CA1. Accordingly, the shrinkage ratio of the base body BD can be adjusted and the occurrence of unevenness and warpage on the upper surface and the lower surface of the base body BD can be reduced. In addition, since the contact area between the magnetic layer 20 and the second vertical wiring 142 is increased, the closeness between the magnetic layer 20 and the second vertical wiring 142 is improved. This is also true of the first vertical wiring 141.
(2-3) According to the second embodiment described above, the diameters of the three columnar portions constituting the second vertical wiring 142 are identical. That is, the maximum dimensions in the direction parallel to the main surface MF of the three columnar portions are identical. Accordingly, in the covering processes that form the three columnar portions, the settings of the sizes of the ranges in which each of the columnar portions is not to be formed can be the same setting. In particular, in the second embodiment described above, the sectional areas of the second vertical wiring 142 in the direction orthogonal to the thickness direction Td are identical. Accordingly, the current flowing through the second vertical wiring 142 can be suppressed from becoming less likely to flow partially. This is also true of the first vertical wiring 141.
(2-4) According to the second embodiment described above, the three columnar portions constituting the second vertical wiring 142 are in direct contact with each other. Accordingly, when the second vertical wiring 142 is configured by a plurality of columnar portions, a via or the like for connecting these columnar portions is not necessary. This is also true of the first vertical wiring 141.
(2-5) According to the second embodiment described above, the lower surface of the inductor wiring 30 is covered with the first insulating portion 171. Accordingly, the insulation of the lower side of the inductor wiring 30 can be ensured.
(2-6) According to the second embodiment described above, the second insulating portion 172 is interposed in the gap between the inductor wirings 30 running in parallel. Accordingly, the insulation between the inductor wirings 30 can be ensured.
The embodiments described above can be modified and implemented as described below. The embodiments described above and the modifications described below can be combined and implemented within the scope in which technical contradiction does not occur.
In the embodiments described above, when the surface of each of the vertical wirings that excludes the upper surface and the lower surface is assumed to be the side surface, the side surface of each of the vertical wirings does not need to make contact with the upper magnetic layer 23. In the inductor component 210 of the example illustrated in
In the embodiments described above, the insulating layer 60 may be omitted. For example, in the example illustrated in
In the embodiments described above, layers made of a material other than the magnetic material may be adopted instead of the intermediate magnetic layer 22 and the lower magnetic layer 21. At least the upper magnetic layer 23 penetrated by the vertical wirings only need to be present. In the example illustrated in
For example, in the example illustrated in
For example, in the example illustrated in
In the embodiments described above, the dimensions in the thickness direction Td of the first vertical wiring and the second vertical wiring do not need to match the dimension in the thickness direction Td of the upper magnetic layer 23. In addition, the upper surfaces of the vertical wirings do not need to be flush with the upper surface of the upper magnetic layer 23. At a minimum, the vertical wirings only need to penetrate the upper magnetic layer 23 and be exposed on the side of the main surface MF of the base body BD. Accordingly, even if the upper surfaces of the vertical wirings are located below the upper surface of the upper magnetic layer 23, it is sufficient that the upper surfaces of the vertical wirings are not completely covered with the upper magnetic layer 23 and are exposed through the main surface MF of the base body BD. When the upper surfaces of the vertical wirings are located above the upper surface of the upper magnetic layer 23, the portions of the vertical wirings below the upper surface of the upper magnetic layer 23 are the penetration portions PP.
In the embodiments described above, the shape of the inductor wiring 30 is not limited to the examples in the embodiments described above. For example, the number of turns of the inductor wiring 30 may be any number and the shape may be substantially a curve with 2.0 turns or more or substantially a straight line with 0 turns. In addition, for example, the inductor wiring 30 may have a substantially meander shape. In the example illustrated in
In addition, for example, the cross section orthogonal to the extension direction of the inductor wiring 30 is not limited to substantially quadrilateral, and the cross section orthogonal to the extension direction of the inductor wiring 30 may be substantially circular or substantially polygonal. In addition, the surface of the inductor wiring 30 may be substantially curved.
In the embodiments described above, the shapes of the vertical wirings when viewed in the thickness direction Td are not limited to the examples in the embodiments described above. For example, the shapes of the vertical wirings when viewed in the thickness direction Td may be substantially elliptic or polygonal.
In the example illustrated in
In the embodiments described above, the shapes of the vertical wirings may be substantially columnar and are not limited to the examples of the embodiments described above. In the example illustrated in
In the example illustrated in
In the example illustrated in
Furthermore, in the example illustrated in
In addition, in the example illustrated in
Furthermore, in the example illustrated in
As in the examples illustrated in
In the embodiments described above, the dimension in the thickness direction Td of the penetration portion PP in each of the vertical wirings is not limited to the examples in the embodiments described above. Accordingly, the dimension in the thickness direction Td of the penetration portion PP may be less than about 100 μm.
In the first embodiment, the ratio of the dimension TV2 in the thickness direction Td of the penetration portion PP to the diameter D2 of the second vertical wiring 42 may be less than about 2.0. However, when the ratio of the dimension TV2 in the thickness direction Td of the penetration portion PP to the diameter D2 of the second vertical wiring 42 is not less than about 2.0, the dimension TV2 in the thickness direction Td of the second vertical wiring 42 is large, so the wiring length of the second vertical wiring 42 can be ensured, which is preferable from the viewpoint of improving the inductance. In addition, when the ratio of the dimension TV2 in the thickness direction Td of the penetration portion PP to the diameter D2 of the second vertical wiring 42 is not less than about 2.1, the wiring length of the second vertical wiring 42 can be further extended, which is preferable from the viewpoint of improving the inductance. This is also true of the second embodiment.
In the embodiments described above, the dimension in the thickness direction Td of the penetration portion PP may be less than about 7 times the maximum dimension TI in the thickness direction Td of the inductor wiring 30.
In the embodiments described above, the maximum dimension TI in the thickness direction Td of the inductor wiring 30 is not limited to the examples in the embodiments described above. Also, the maximum dimension TI in the thickness direction Td of the inductor wiring 30 may be less than about 10 μm or may be more than about 50 μm. The maximum dimension TI in the thickness direction Td of the inductor wiring 30 of not less than about 10 μm and not more than about 50 μm (i.e., from about 10 μm to about 50 μm) is desirable in terms of increasing the inductance.
When each of the vertical wirings includes a plurality of columnar portions, the number of columnar portions is not limited to the example in the second embodiment described above. For example, the first vertical wiring 141 may include two columnar portions or may include not less than four columnar portions. In addition, for example, all of the central axes of the plurality of columnar portions may be on the same straight line. In addition, for example, all of the dimensions in the thickness direction Td of the plurality of columnar portions may be the same or may be different from each other. Furthermore when, for example, the first vertical wiring includes three or more columnar portions, the maximum dimensions in the directions parallel to the main surfaces MF of at least two of the columnar portions may be the same dimension, and the maximum dimensions in the directions parallel to the main surfaces MF of the other one or more columnar portions may be different from each other.
The materials of the vertical wirings are not limited to the examples in the embodiments described above. For example, the materials of the vertical wirings may be different from the material of the inductor wiring 30. For example, the material of the inductor wiring and the materials of the vertical wirings may be any conductive material and may be copper, silver, gold, aluminum, or alloy containing these metals.
In the embodiments described above, the dimensions in the thickness direction Td of the lower magnetic layer 21, the intermediate magnetic layer 22, and the upper magnetic layer 23 are not limited to the examples in the embodiments described above. For example, in the first embodiment, when the dimension in the thickness direction Td of the lower magnetic layer 21 is not less than the dimension in the thickness direction Td of the upper magnetic layer 23, the inductor wiring 30 can be covered with a reasonable amount of the magnetic layer 20 in the thickness direction Td. As a result, noise from the inductor wiring 30 in the inductor component 10 can be suppressed from leaking outside the inductor component 10.
In the embodiments described above, the dimension TBD in the thickness direction Td of the base body BD is not limited to the examples in the embodiments described above. For example, in the first embodiment, the dimension TBD in the thickness direction Td of the base body BD may be more than about 500 μm. Even in this case, it is possible to suppress the volume of the upper magnetic layer 23 from becoming excessively small due to the presence of the vertical wirings.
In the embodiments described above, the layers that constitute the inductor component may be integrated with each other or configured as separate bodies. For example, in the first embodiment, an interface may be present between the first layer L1 and the second layer L2 and an interface may be present between the third layer L3 and the fourth layer L4 by integrating the second layer L2 and the third layer L3 with each other with no interface and configuring the first layer L1 and the fourth layer L4 as separate bodies.
In the embodiments described above, the inductance obtained from the inductor component when a small signal current at a frequency of 100 MHz flows from the first external terminal 51 to the second external terminal 52 through the first vertical wiring, the inductor wiring 30, and the second vertical wiring is desirably not less than about 1 nH and not more than about 10 nH (i.e., from about 1 nH to about 10 nH). The inductance is measured by the network analyzer E5071 (manufactured by Keysight) or an equivalent, the S (scattering) parameters at a measurement frequency of 100 MHz is measured via the shunt-through method, and the obtained value is converted to inductance value. However, the effects of jigs are removed by de-embedding and short-circuit correction. The inductor component expected to be used at high frequencies is preferable because the wiring length of the conductive portion including the single-layer inductor wiring 30 and the vertical wirings is sufficient to obtain the inductance in the range described above. In addition, the inductance described above can contribute to the improvement of the efficiency of a DC-DC converter when, for example, the inductor component is used as a component to be built into the DC-DC converter.
While preferred embodiments of the disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the disclosure. The scope of the disclosure, therefore, is to be determined solely by the following claims.
Number | Date | Country | Kind |
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2020-142632 | Aug 2020 | JP | national |